1. Field of the Invention
The present invention relates to a torque variation absorbing device for an engine.
2. Description of the Prior Art
An engine for an automobile or an aircraft is provided with a torque variation absorbing device for transmission of the power of the engine.
A known type of torque variation absorbing device is disclosed in laid-open Japanese patent application 59-166723. The known device has two inertia members, i.e., a first flywheel member which is rotatably connected to a crankshaft of an engine and a second flywheel member which is connected to a follower means, e.g., a transmission member driven by a clutch member, and is rotatable with respect to the first flywheel member. Between the first and the second flywheel members, a spring mechanism, a damping and torque limiting mechanism and a hysteresis mechanism are provided.
In this device, the rotation of the crankshaft is transmitted to the second flywheel member through the first flywheel member, the spring mechanism, the damping and torque limiting mechanism and the hysteresis mechanism. Thus, the torque variation is absorbed by the vibration system defined by these members. The hysteresis mechanism comprises a first driving plate, a friction plate and a second drive plate. A hysteresis effect is provided by friction of the friction plate with respect to other members.
However, in the above described device, the hysteresis effect can create an unstable condition as friction force is reduced due to wear of the friction plate.